Austenite stainless steel which is excellent in its anti-abrasion property and easy to work on, is widely used for spectacle frames, watch casings, watch bracelets, other decorative bracelets, and necklaces. These articles are often laid over selectively at their outer surfaces by an alloy of precious metals of a desired purity such as for example gold 18 carats fine and 14 carats fine, in order to enhance their decorative effects.
Austenite stainless steel materials compounded with an alloy of precious metals such as gold alloy to have an overlay or inlay for example is conventionally produced by so-called separate plating or masking plating method. The separate plating method is not economically suited for continuously processing small dimensional goods such as articles of the above-mentioned kind in an industrially acceptable scale. Hence, the masking method is more conventionally employed, in which those articles are masked at their outer surfaces other than those specific portions where they are to be plated, and the said specific or unmasked portions are electrolytically plated by a desired precious metal alloy. As an other method for compounding austenite stainless steel decorative articles with a gold alloy, they are overlaid or inlaid by binding thereto a thin sheet of gold 18 carats fine for example by means of a silver hard solder.
In the former method, viz., mask-plating method, however, it is hard to effectively compound or plate a surface of the stainless steel base with an even and very dense layer of precious metal alloy of a thickness more than a limited amount of about 1.5.mu., because its alloy constituents are differently and unevenly ionized in a single electrolytic solution, and produce cracks or pin holes in the constituents precipitated onto the surface as they alloy. These cracks and pin holes weaken mechanical strength, particularly anti-abrasion property of the decorative alloy tinsel. The latter method, viz., soldering method though which can overlay or inlay a precious metal alloy of any desired thickness onto the basic stainless steel, has also drawbacks that it is extremely laborious and difficult to have a minute piece of thin alloy metal sheet put in place on the steel and overlaid or inlaid firmly thereto by solders, and that the solders which have been employed in cladding the thin sheet piece of alloy to the basic sheet, corrode comparatively soon and decrease sparkling effect given by the decorative alloy to an article.